(a) Field of the Invention
Exemplary embodiments of the invention relate to a display device including a touch sensor.
(b) Description of the Related Art
A liquid crystal display “(LCD”) is one of the most widely used types of flat panel display. The LCD typically includes two display panels in which field-generating electrodes, such as a pixel electrode and a common electrode, for example, are provided, and a liquid crystal (“LC”) layer disposed between the field-generating electrodes. The LCD displays images by applying voltages to the field-generating electrodes to generate an electric field in the LC layer that determines the orientations of LC molecules therein to adjust polarization of incident light.
The LCD may operate with various input devices. More particularly, the LCD including a touch panel as the input device thereof has been used.
The touch panel device is a device that allows a machine, such as a computer, for example, to perform a command by touching a screen of a touch panel with a finger or a touch pen (or stylus) to write or draw characters or execute icons. A display device attached with the touch panel thereto or including the touch panel therein determines whether or not a user's finger or a touch pen touches the screen, and information on a touch position to thereby input a command.
The touch panel is typically divided into a resistive type, a capacitive type, an electro-magnetic type (“EM”), and an optical type in accordance with a touch detection method.
The capacitance type of touch panel includes a film formed with a transparent electrode, and touch existence, and touch positions may be determined by measuring a voltage change by a contact with a finger or a conductive material while a voltage is applied to the transparent electrode.
The touch panel of the capacitance type typically includes two transparent conductive layers for sensing on the display panel and an insulating layer therebetween, or an additional metal layer for sensing inside the display panel and the insulating layer must be formed, such that the manufacturing process is complicated.